Mr Wieser wrote in a note: “We would not be surprised if some assets were pruned to make the company more manageable, or perhaps invest to more clearly establish a focus in certain areas that are likely to support improved long-term growth trends.”

Alex deGroote at Cenkos Securities said divisions such as Kantar, a market research business, could be sold and be worth as much as £3.5bn.

In March WPP reported its weakest annual results since the financial crisis, with Sir Martin describing 2017 as “not a pretty year” for the company even though pre-tax profits were just over £2bn.

Meanwhile, the Financial Times reported that the 73-year-old is free to start a rival company because he never had a non-compete agreement, according to WPP insiders.

Sir Martin departed following claims of personal misconduct. WPP had also hired a law firm to investigate claims of financial impropriety against him, but the company said that probe had concluded.